Early Diagnosis of Tuberculosis and Its Prevention in Preschool Children from 'Risk' Groups

The dissertation is devoted to the development of methods for early diagnosis of tuberculosis infection and improvement of preventive measures in preschool children belonging to "risk" groups. The research was carried out at the Novosibirsk State Medical Academy and is aimed at solving urgent problems of phthisiopediatrics associated with the declining diagnostic value of traditional tuberculin diagnostics and the need to objectify early detection of primary tuberculosis infection in preschool children.

In the work, a modified immunological method — modified blast transformation lymphocyte reaction to tuberculin (mBTLR on PPD-L) — is proposed, which allows differentiation of paraallergy from infectious allergy, detection of an active tuberculosis process, and objective assessment of the effectiveness of specific therapy. The effectiveness of bioptron light therapy as a method of preventive treatment of children first infected with Mycobacterium Tuberculosis was also studied, and a comprehensive health improvement program for children from "risk" groups, implementable in the conditions of a specialized sanatorium preschool institution, was developed.

Relevance of the Problem. In connection with the increase in tuberculosis morbidity, contemporary literature continues to widely discuss such urgent issues as timely identification of the early period of tuberculosis infection in children and improvement of preventive measures taking into account age-related, social, and epidemiological factors [35, 47, 141, 235, 237].

Great attention is devoted to questions of tuberculosis infection diagnosis. The main method of early detection of tuberculosis infection in our country remains tuberculin diagnostics [6, 165, 175]. In recent years, its diagnostic value has been declining: the detection rate of active tuberculosis process in children by tuberculin diagnostics amounts to 0.22 per 1000 examined, in adolescents — 0.12, by fluorography — 0.44 [175]. Interpretation of Mant test results is often complicated by the presence of foci of chronic nonspecific infection, allergic diseases [175, 207] in the child. Therefore, in phthisiopediatrics there is a great need for reliable special tests allowing assessment of the tension of antituberculous immunity, differentiation of infectious allergy from paraallergy, and determination of the probability of local forms of tuberculosis in infected children.

The most promising for early detection of tuberculosis infection are specific immunological methods with quantitative assessment of results, in combination with differentiated investigation of organism reactivity.

The problem of effectiveness of preventive antituberculous measures is also urgent. Among modern physiotherapeutic methods possessing immunomodulating action, bioptron light therapy belongs to one [43, 44, 45, 51, 52, 126]. The great attention devoted to polarized light is explained by the following facts: a wide spectrum of therapeutic action; absence of contraindications; the process is carried out contactlessly and sterily; possibility of combination with other traditional methods of treatment. Light therapy by the "Bioptron" method is applied: in dermatology, in rheumatology, sports medicine, and in surgery. At the same time, the effectiveness of using bioptron light therapy in phthisiology has not been studied. Therefore, it appears expedient to study the possibility of using this method for preventive treatment of children from "risk" groups for tuberculosis in a complex of preventive measures in specialized preschool institutions.

The aim of the study: development of an additional method for early diagnosis of tuberculosis infection in preschool children and a complex of therapeutic and health improvement measures for children from "risk" groups for tuberculosis in specialized preschool institutions. Tasks of the study: 1. To study the diagnostic significance of modified blast transformation lymphocyte reaction to tuberculin stimulation (mBTLR on PPD-L) in preschool children with positive Mant test results at 2 TU PPD-L for a differentiated approach to preventive treatment.

2. To evaluate the possibility of using mBTLR on PPD-L as an additional diagnostic criterion of activity of the tuberculosis process and an objective indicator of effectiveness of specific therapy.

3. In preschool children first infected with MTB, to study the effectiveness of light therapy by the "Bioptron" method in comparison with preventive treatment by antituberculous preparations.

4. To develop and determine the effectiveness of a health improvement program for children from "risk" groups for tuberculosis in specialized preschool institutions.

Scientific Novelty of the Research. For the first time for early detection of tuberculosis infection in preschool children, a modified immunological method of quantitative determination of results based on the blast transformation lymphocyte reaction with a specific mitogen (tuberculin) was applied.

The effect of bioptron light therapy on the condition of preschool children first infected with Mycobacterium Tuberculosis was studied, and the effectiveness of this method in preventing the development of local forms of tuberculosis was proven.

A program "Complex Health Improvement of Children in Conditions of a Specialized Preschool Institution" was developed, and an optimal organizational structure of a sanatorium preschool institution was recommended.

Practical Significance. Use of a highly specific, highly sensitive modified immunological method (mBTLR on PPD-L) in clinical practice provides an opportunity to objectify the diagnosis of activity of specific inflammation, assess the effectiveness of specific therapy, conduct differential diagnosis of infectious allergy and paraallergy in preschool children, and develop a differentiated approach to preventive treatment of children first infected with MTB.

Inclusion of bioptron light therapy in a complex of therapeutic and health improvement measures prevents the development of an active tuberculosis process.

Implementation of the developed complex program of health improvement for children from "risk" groups for tuberculosis in specialized preschool institutions made it possible to reduce acute somatic morbidity by 3.4 times, reduce sensitivity to tuberculin by 1.4 times, and prevent the development of local forms of tuberculosis.

Positions to be Defended.

1. In children with positive Mant test results at 2 TU PPD-L, mBTLR on PPD-L allows differentiation of paraallergy from infectious allergy in preschool children with subsequent selection of groups for preventive treatment, detection of an active tuberculosis process, and objective assessment of the effectiveness of specific therapy.

2. Bioptron light therapy in a complex of therapeutic and health improvement measures in preschool children first infected with MTB, not registered at a dispensary for contact, prevents the development of local forms of tuberculosis.

3. The developed and introduced into the practice of specialized preschool institutions complex of therapeutic and health improvement measures makes it possible to prevent the development of tuberculosis in children from "risk" groups. Implementation of the Research Results. For early diagnosis of tuberculosis infection in children, the modified blast transformation lymphocyte reaction with a specific mitogen (tuberculin) was introduced into clinical practice of healthcare in the Omsk Region (Regional Specialized Children's Tuberculosis Clinical Hospital of the City of Omsk, City Anti-Tuberculosis Dispensaries of the City of Omsk No. 1, 2, 3, 4, 5, 6); an informational letter "Diagnostic Criteria of Level of Infection with Mycobacterium Tuberculosis in Children" was prepared, approved by the Department of Healthcare of the Administration of the City of Omsk on January 23, 2003.

Complex health improvement according to the program for preschool children from "risk" groups is carried out in the specialized institution "Sanatorium Nursery-Kindergarten No. 30 of the City of Omsk".

Research materials are used in the educational process at the Department of Phthisiology and Phthisiogenic Surgery of the Omsk State Medical Academy.

Validation of the Results. The materials were presented at scientific and practical conferences of physicians and researchers dedicated to the 75th and 80th anniversaries of the phthisiatric service of the Omsk Region (Omsk, 1998, 2003); a scientific and practical conference dedicated to the 80th anniversary of Omsk State Medical Academy "Infectious Diseases of Man" (Omsk, 2001); a scientific and practical conference dedicated to the 90th anniversary of Academician of RAMN, Professor V.P. Bisyarina (Omsk, 2002); the 3rd Congress of the European Region and the 14th National Congress on Diseases of the Respiratory Organs (Moscow, 2004); an interregional scientific and practical conference "Modern Problems of the Fight against Tuberculosis" (Perm, 2005).

Publications. Eight works on the dissertation topic have been published, including one in a peer-reviewed journal.

Volume and Structure of the Dissertation. The dissertation is presented on 158 pages of computer text, illustrated with 32 tables and 7 figures.

The work consists of an introduction, a literature review, a chapter on materials and methods of research, a chapter on results of own research, a conclusion, conclusions, and practical recommendations. The bibliographic reference list includes 198 sources in Russian and 43 in foreign languages.

1. LITERATURE REVIEW